diff --git a/net/ethtool/strset.c b/net/ethtool/strset.c
index 8d1c1a9bbd95..5f9795ffca6b 100644
--- a/net/ethtool/strset.c
+++ b/net/ethtool/strset.c
@@ -324,6 +324,8 @@ static int strset_reply_size(const struct ethnl_req_info *req_base,
 	int len = 0;
 	int ret;
 
+	len += nla_total_size(0); /* ETHTOOL_A_STRSET_STRINGSETS */
+
 	for (i = 0; i < ETH_SS_COUNT; i++) {
 		const struct strset_info *set_info = &data->sets[i];